Answer:
y = -|x-2| (*)
2 cases:
case 1: for x≥2 <=> |x-2| = x-2
(*) <=> y = - (x-2)
<=> y = -x+2
<=> x+y = 2
case 2: for x>2 <=> |x-2| = 2-x
(*) <=> y = -(2-x)
<=> y = x-2
<=> x-y = 2
since there are 2 variables but just one equation, we cannot find the exact values of x and y. Instead, we can find some kind of connection between them.